Radio frequency transfer switch

ABSTRACT

A radio frequency transfer switch is provided which includes a pair of spaced apart annular fixed contact elements and a pair of movable contact discs carried by an axially reciprocable shaft which is fluid motor actuated to move the contact discs into and out of engagement with the fixed annular contacts. The fixed annular contacts are supported by plate means and fluid cooling tube means are disposed against the plate means and in surrounding relationship with respect to the fixed annular contacts.

O United States Patent [151 3,668,354 Meermans 1 June 6, 1972 54] RADIO FREQUENCY TRANSFER 1,294,053 2/1919 Cole ...200/l66 BD SWITCH 3,261,953 7/1966 Tilman et al. ..200/l66 K 3,244,833 4/1966 Gillett et al. ..200/ 166 K [72] Meermans stmngsvme 9' 2,794,879 6/1957 Clason ..200/1 66 BD [73] Assignee: Park-Ohio Industries, Inc., Cleveland,

' Ohio Primary Examiner-David Smith, Jr. I I Filed: Dec. 4 1970 AttorneyMeyer, Tilberry and Body [21] Appl. No.: 95,212 [57] ABSTRACT A radio frequency transfer switch is provided which includes a Cl 153 2 200/166 pair of spaced apart annular fixed contact elements and a pair 200/ 144 B of movable contact discs carried by an axially reciprocable [51] Int. Cl. ..H0lh 3/00 Shaft whlch 1S fluld momr actumed to move the Contact dlscs [58] Flew Search" 166 144 166 BD; into and out of engagement with the fixed annular contacts 333/97 S The fixed annular contacts are supported by plate means and fluid cooling tube means are disposed against the plate means 1 References Cited and in surrounding relationship with respect to the fixed annu- UNITED STATES PATENTS 3,017,479 1/1962 Jennings ..200/16 A 17 Claims, 6 Drawing Figures PATENTEnJuu 6 m2 SHEET 1 (IF 3 RONALD A. MEERMANS BY Maya, 7% 8 Body ATTORNEYS PATENTEUJUH 6 I972 SHEEI 2 OF 3 m oI INVENTOR. RONALD A. MEERMANS BY Mega, 7M 23 Body ATTORNEYS PATENTEnJun 6|972 3,668,354

SHEET 30F 3 FIG. 4

FIG. 6

INVENTOR.

RONALD A. MEERMANS BY ATTORNEYS is lost in this type-of switch, the electrical clearance is too small. Further, the switch contact surfaces in previous radio frequency transfer switches are far removed from the cooling source, whereby there is a limitation with respect to the extent to which efiective cooling can be achieved. The radio frequency transfer switch of the present invention advantageously overcomes the disadvantages of switches of this character heretofore known.

An object of the invention is the provision of a compact radio frequency transfer switch wherein the structure of fixed and movable contact components of the switch provides for maximum surface contact between these components, even in the event of a slight misalignment therebetween.

Another object of the present invention is the provision of a compact radio frequency transfer switch wherein the structural relationship between the current carrying components of the switch provides for these components to be more effectively and efficiently cooled than heretofore possible.

Yet another object of the present invention is the provision of a compact radio frequency transfer switch wherein the contact surfaces of fixed contacts of the switch are in close heat transfer relationship with cooling means for the switch thus to provide a more efficient and effective cooling of the contacts.

Still afurther object is the provision of a radio frequency transfer switch wherein movable contact components of the switch are maintained in spaced apart and electrically conductive relationship by means defining a heat sink for dissipation of heat generated during use of the switch device.

Other objects will in part be obvious and in part more fully pointed out hereinafter.

With reference to the drawing wherein there is illustrated a preferred embodiment of the present invention;

FIG. I is a plan view of a pair of radio frequency transfer switches of the present invention mounted on a common support plate and illustrating fluid motor means on one side of the support plate for actuating the switches;

FIG. 2 is an elevational view of the assembly of FIG. 1 looking toward the side of the mounting plate on which the fluid motors are disposed;

FIG. 3 is a side elevation view, along the line 3-3 of FIG. 2;

FIG. 4 is a sectional elevation of a portion of the fixed and partially in section, taken movable contact components of the switch of the present invention, illustrating the movable contacts in engagement with the fixed contacts;

FIG. 5 is a sectional view of the conducting and spacing component disposed between the movable contacts, taken along the line 5-5 ofFlG. 4; and

FIG. 6 is a plan view of a preferred form of the movable contact disc of the switch of the present invention.

' Referring now to FIGS. 1, 2 and 3 of the drawing, there is illustr'ated a radio frequency transfer switch mounting assembly comprised of a pair of radio frequency transfer switches 10 of the present invention, each mounted on a common mounting plate 11. Each switch 10, as best illustrated in FIG. 3 of the drawing, includes support plate means 12 and support plate means 13 of copper. Support plate means 12 is common to both switches 10 and is suitably secured, such as by screws 14, to mounting plate 11 which is of suitable insulating material. Support plate means 13 of each switch is supported in substantially parallel spaced apart relationship with respect to support plate means 12 by means of a plurality of elements of suitabolt fasteners 17.

ble insulating material. Insulator elements I5 are fastened at one end thereof to support plate means 13 by means of nut and bolt fasteners 16. The other ends of insulator elements 15 are suitably secured to mounting plate 11 Annular fixed contact means 18 and 19 are suitably mounted on support plate means 12 and 13, respectively. The annular contacts are of conductive, non-magnetic material and preferably are silver plated to lessen the resistance to current flow therethrough. Further, contacts 18 and 19 are disposed in coaxial relationship with respect to one another and with respect to openings 20 and 21 in support plates 12 and 13, respectively, and opening 11a in plate 11. The fixed contacts 18 and 19 further having corresponding contact faces 22 and 23 which, preferably, are contoured to define contact seats which are concave and disposed at an angle of approximately 3 with respect to a plane passing transversely through the axis of the annular contacts, as illustrated in FIG. 4.

Movable contact means 30 is provided for bridging the space between fixed contacts 18 and 19. Movable contact means 30, as illustrated in FIGS. 3 and 4, includes reciprocable disc contact elements 32 and 33 and conductor and spacer means 34 disposed between disc contact elements 32 and 33. Disc contact elements'32 and 33 are in the form of apertured metallic discs of conductive, resilient, non-magnetic material and preferably are silver plated so as to be less resistive to current flow therethrough.

Discs 32 and 33 are maintained in axially spaced apart and conductively inter-connected relationship by means of conductor and spacer means 34. The conductor and spacer means preferably is formed of conductive, non-magnetic material and is provided with a longitudinally extending threaded aperature 40 to receive threaded shaft means 31. Shaft means 31 is provided with threads 38 for cooperative engagement with threaded aperture 40 and to receive a nut 39 which cooperates with lock washer 41 to retain the conductor and spacer means and disc contact 32 in place on the shaft means. Bolt means 42 and lock washer 42a cooperate to removably fasten disc contact 33 to the opposite end of conductor and spacer means 34. The length of the threads 38 along the shaft means 31 and the length of threaded aperture 40 is such that the discs 32 and 33 and conductor and spacer means 34 can be axially adjusted as a unit relative to shaft means 31 for the purpose set forth hereinafter. The conductor and spacer component is of a length to accurately space disc contacts 32 and 33 a distance equal to the axial distance between annular fixed contacts 18 and 19, whereby the disc contacts will engage the corresponding annular contacts simultaneously.

Conductor and spacer component 34 preferably is longitudinally slotted to define longitudinally extending, radially projecting fins 43, as illustrated in FIGS. 3 and 4. These fins increase the surface area of the conductor and spacer component exposed to ambient air and thus facilitate dissipating heat generated during use of the switch unit. Obviously, any number of fins could be provided, and the number and cross sectional configuration thereof depicted in FIG. 4 is merely illustrative of a suitable arrangement.

The discs are flexible so as to permit the outer marginal edges thereof to flex against their inherent resilient bias upon engagement with the corresponding fixed annular contact, thus to seat with spring bias substantially flush against the concave faces of the annular contacts, as illustrated in FIG. 4.

Flexing of the outer periphery of the resilient disc upon engagement with the concave face of the corresponding annular contact assures a full and positive engagement between the surface of the fixed and movable contacts. Flexing of the contact discs can be advantageously enhanced by slitting the disc radially such as in the manner depicted in FIG. 6, for example. In this respect, deep slits 35 and shallow slits 36 are provided about the periphery of the disc in alternating fashion.

Adjacent deep slits 35 define individually flexible fingers 37, and shallow slits 36 divide the outer ends of each finger 37 into individually flexible finger sections 37a and 37b. It will be by means of nut and appreciated that such a disc structure not only provides for assuring substantially full face contact between the coaxial disc and annular fixed contact surfaces when the latter surfaces are in true alignment, but also provides for such contact when there exists a misalignment between the fixed and movable contacts.

Shaft means 31 is axially reciprocated by motor means 50 in the form of a fluid cylinder 51 having a piston 52 therein and mounted on the inner end of piston rod means 53 which preferably is defined by an extension of shaft means 31. It is to be clearly understood, however, that the shaft means and piston rod means could be separate elements suitably interconnected either interiorly or exteriorly of the cylinder Cylinder 51 is mounted on plate 11 by means of non-magnetic metal brackets 54 so that the axis'of the cylinder and thus the axis of shaft means 31 is coaxial with regard to the axes of fixed contacts 18 and 19.

.Cylinder 51 is provided with fluid openings 55 and 56 adjacent opposite ends thereof and each opening is connected to, a source of operating fluid such as air through corresponding lines 57 and 58 which function both as supply and exhaust lines. Suitable control means, not illustrated,are operable to control fluid flow to and from cylinder 51 to positively drive piston 52 and thus shaft means 31 in opposite directions. More particularly, in a switch closing operating air under pressure is introduced through opening 55in the cylinder behind piston 52 to drive the piston and thus shaft means 31 toward contact closing position, and simultaneously air is exhausted ahead of piston 52 through cylinder opening 56. When the switch contacts are to be opened, air under pressure is introduced through cylinder opening 56 and the air behind piston 52 is exhausted-through opening 55, whereby shaft means 31 is drivenin the contact opening direction. The piston stroke is such that the disc contacts will engage and be flexed to substantially the same degree so as to seat against the corresponding fixed contacts in flush engagement with the concave surfaces thereof. By providing for the disc contacts and spacer and conductor component 34 to be axially adjustable relative to the shaft means, as described hereinabove, the desired seating relationship can readily be achieved in the event that an adjustment in this respect is necessary.

In the structure thus far described, it will be appreciated that closure of contact discs 32 and 33 against annular contacts 18 and 19 results in establishing a path for current flo'w from annular contact 18 to disc contact 32 and thence to conductor and spacer sleeve 34, disc contact 33 and annular contact 19. Current input to annular contact 18 may be achieved through use of any suitable conductor means such as line 59, and current output from annular contact may be achieved by use of conductor means such as line 60. Cooling means is provided for both the input and output sides of the switch in the form of tubing means through which a suitable coolant is circulated. In the embodiment illustrated herein wherein two switch assemblies are supported on a common mounting plate, the coolant tubing on the input side of the switches includes two sections 61 and 62 each extending from a common coolant inlet fitting 63 and about the annular fixed contacts 18 on support plate means 12. It is to be understood, however, that only one, or more than two switch units may be associated with a common mounting plate and that the coolant tube means can be appropriately configured to provide for the desired relationship between the tube means and annular con tact elements, namely to provide for the coolant tube means to extend about or substantially about the annular contacts to enhance cooling of the annular contacts as well as the support and mounting plate means. Tubing sections 61 and 62 are connected with corresponding coolant outlet fittings 64 and 65, whereby coolant introduced through fitting 63 is continuously circulated through and out of the tubing sections.

' The switch cooling means further includes tubing sections 66 and 67 mounted on plate means 13 and disposed in surrounding relationship with respect to the corresponding one of the annular fixed contacts 19. Tubing sections 66 and 67 have corresponding coolant inlet and outlet fittings 68, 69 and 70, 71, respectively, associated therewith. Cooling tube sections 66 and 67 may be connected individually to separate coolant circulating systems but preferably are interconnected with sections 61 and 62 in a manner whereby only a single circulating system is required. In this respect, coolant outlet fittings 64 and 65 of tubing sections 61 and 62 are'connected respectively through hose means 72 and 73 to the coolant inlet fittings 68 and 70 of tubing sections 66 and 67, respectively. Hose means 72 and 73 are of non-conductive material such as rubber or plastic, thus to assure electrical isolation of the input and output sections of the switch. Preferably, hose means 72 and 73 each extend laterally outwardly from the corresponding switch unit and into a coil configuration in which the hose extends through openings 74 in plate 11 and thus is supported by mounting plate 11. This configuration provides for exposing a considerable length of tubing to ambient air in a compact area to facilitate dissipation of heat absorbed by the coolant on the input side of the switch assembly before the coolant enters the tubing associated with the output side of the switch assembly. Again, it will be clearly understood that the coolant circulating path through the coiled hose configuration may be employed with a single input-output switch unit as well as with a plurality of input-output assemblies.

The invention has been described in detail sufficient for one skilled in the art of radio frequency switches to understand the invention. Modifications of the preferred embodiment will, of

course, occur to those reading and understanding the foregoing description, and it is my intention to include all such modifications as part of my invention insofar as they come within the scope of the appended claims.

I claim:

1. A radio frequency transfer switch comprising support plate means supported in substantially parallel spaced apart relationship, fixed annular contact means on each of said plate means, tubular coolant circulating means on said plate means and extending about the corresponding one of said fixed contact means to facilitate circulation of fluid coolant to dissipate heat from said fixed contact means, said fixed contact means being coaxial with respect to one another and having axially spaced apart contact faces, movable contact means including reciprocable shaft means coaxial with said fixed contact means and disc contact elements each corresponding to one of said annular fixed contact means, said movable contact means further including conductor and spacer means disposed between said disc contact elements and conductively interconnecting and spacing said disc contact elements apart a distance substantially equal to the distance between said contactfaces of said fixed contact means, and means for imparting reciprocable movement to said shaft means to simultaneously move said disc elements either into or out of engagement with the corresponding one of said fixed contact means to selectively connect or disconnect said fixed contact means for current flow therebetween.

2. A radio frequency transfer switch of the character set forth in claim 1, wherein said contact faces of said annular fixed contact means are each inclined to define a concave seat for the corresponding one of said disc contact elements.

3. A radio frequency transfer switch of the character set forth'in claim 2, wherein the incline of said contact faces is 3 relative to a plane transverse to the axis of said openings.

4. A radio frequency transfer switch of the character set forth in claim 2, wherein said disc contact elements are provided with slit means to facilitate deflection of the discs into substantial conformity with said concave seats of said fixed contact means upon engagement therebetween.

5. A radio frequency transfer switch of the character set forth in claim 4, wherein said slit means includes a plurality of slits extending radially inwardly toward the axis of said shaft means from the periphery of said disc contact elements, adjacent ones of said slits varying in radial depth.

6. A radio frequency transfer switch of the character set forth in claim 1, wherein said conductor and spacer means and said disc contact elements are axially adjustable as a unit relative to said shaft means.

7. A radio frequency transfer switch of the character set forth in claim 6, wherein said conductor and spacer means is provided with cooling fin means.

8. A radio frequency transfer switch of the character set forth in claim 4, wherein said conductor and spacer means and said disc contact elements are axially adjustable as a unit relative to said shaft means.

9. A radio frequency transfer switch of the character set forth in claim 8, wherein said conductor and spacer means is provided with longitudinally extending cooling fin means.

10. A radio frequency transfer switch of the character set forth in claim 4, wherein said means for imparting reciprocable movement to said shaft means includes fluid motor means.

11. A radio frequency transfer switch of the character set forth in claim 7, wherein said means for imparting reciprocable movement to said shaft means includes fluid motor means.

12. A radio frequency transfer switch of the character set forth in claim 9, wherein said means for imparting reciprocable movement to said shaft means includes fluid motor means.

13. A radio frequency transfer switch comprising support plate means supported in substantially parallel spaced apart relationship, fixed annular contact means on each of said plate means, said fixed contact means being coaxial with respect to one another and having axially spaced apart contact faces, movable contact means including reciprocable shaft means coaxial with said fixed contact means and disc contact elements each corresponding to one of said annular fixed contact means, said movable contact means further including conductor and spacer means disposed between said disc contact elements and conductively interconnecting and spacing said disc contact elements apart a distance substantially equal to the distance between said contact faces of said fixed contact means, means removably and adjustably interconnecting said conductor and spacer means and said disc contact elements said shaft means for said conductor and spacer means and said disc contact elements to be removable from and longitudinally adjustable relative to said shaft means when interconnected therewith, and means for imparting reciprocable movement to said shaft means to simultaneously move said disc elements either into or out of engagement with the corresponding one of said fixed contact means to selectively connect or disconnect said fixed contact means for current flow t therebetween.

14. A radio frequency transfer switch of the character set forth in claim 13, wherein said contact faces of said annular fixed contact means are each inclined to define a concave seat for the corresponding one of said disc contact elements.

15. A radio frequency transfer switch of the character set forth in claim 14, wherein said disc contact elements are provided with slit means to facilitate deflection of the discs into substantial conformity with said concave seats of said fixed contact means upon engagement therebetween.

16. A radio frequency transfer switch of the character set forth in claim 15, wherein said conductor and spacer means is provided with longitudinally extending cooling fin means.

17. A radio frequency transfer switch of the character set forth in claim 13, wherein said means releasably and adjustably interconnecting said conductor and spacer means and said disc contact elements with said shaft means includes thread means on said shaft means, a cooperatively threaded axial bore in said conductor and spacer means to receive said shaft thread means, and means for releasably interengaging said conductor and spacer means and said shaft means in a desired position of said conductor and spacer means longitudinally of said shaft means. 

1. A radio frequency transfer switch comprising support plate means supported in substantially parallel spaced apart relationship, fixed annular contact means on each of said plaTe means, tubular coolant circulating means on said plate means and extending about the corresponding one of said fixed contact means to facilitate circulation of fluid coolant to dissipate heat from said fixed contact means, said fixed contact means being coaxial with respect to one another and having axially spaced apart contact faces, movable contact means including reciprocable shaft means coaxial with said fixed contact means and disc contact elements each corresponding to one of said annular fixed contact means, said movable contact means further including conductor and spacer means disposed between said disc contact elements and conductively interconnecting and spacing said disc contact elements apart a distance substantially equal to the distance between said contact faces of said fixed contact means, and means for imparting reciprocable movement to said shaft means to simultaneously move said disc elements either into or out of engagement with the corresponding one of said fixed contact means to selectively connect or disconnect said fixed contact means for current flow therebetween.
 2. A radio frequency transfer switch of the character set forth in claim 1, wherein said contact faces of said annular fixed contact means are each inclined to define a concave seat for the corresponding one of said disc contact elements.
 3. A radio frequency transfer switch of the character set forth in claim 2, wherein the incline of said contact faces is 3* relative to a plane transverse to the axis of said openings.
 4. A radio frequency transfer switch of the character set forth in claim 2, wherein said disc contact elements are provided with slit means to facilitate deflection of the discs into substantial conformity with said concave seats of said fixed contact means upon engagement therebetween.
 5. A radio frequency transfer switch of the character set forth in claim 4, wherein said slit means includes a plurality of slits extending radially inwardly toward the axis of said shaft means from the periphery of said disc contact elements, adjacent ones of said slits varying in radial depth.
 6. A radio frequency transfer switch of the character set forth in claim 1, wherein said conductor and spacer means and said disc contact elements are axially adjustable as a unit relative to said shaft means.
 7. A radio frequency transfer switch of the character set forth in claim 6, wherein said conductor and spacer means is provided with cooling fin means.
 8. A radio frequency transfer switch of the character set forth in claim 4, wherein said conductor and spacer means and said disc contact elements are axially adjustable as a unit relative to said shaft means.
 9. A radio frequency transfer switch of the character set forth in claim 8, wherein said conductor and spacer means is provided with longitudinally extending cooling fin means.
 10. A radio frequency transfer switch of the character set forth in claim 4, wherein said means for imparting reciprocable movement to said shaft means includes fluid motor means.
 11. A radio frequency transfer switch of the character set forth in claim 7, wherein said means for imparting reciprocable movement to said shaft means includes fluid motor means.
 12. A radio frequency transfer switch of the character set forth in claim 9, wherein said means for imparting reciprocable movement to said shaft means includes fluid motor means.
 13. A radio frequency transfer switch comprising support plate means supported in substantially parallel spaced apart relationship, fixed annular contact means on each of said plate means, said fixed contact means being coaxial with respect to one another and having axially spaced apart contact faces, movable contact means including reciprocable shaft means coaxial with said fixed contact means and disc contact elements each corresponding to one of said annular fixed contact means, said movable contact means further including conductor and spacer means disposed between said disc contact Elements and conductively interconnecting and spacing said disc contact elements apart a distance substantially equal to the distance between said contact faces of said fixed contact means, means removably and adjustably interconnecting said conductor and spacer means and said disc contact elements with said shaft means for said conductor and spacer means and said disc contact elements to be removable from and longitudinally adjustable relative to said shaft means when interconnected therewith, and means for imparting reciprocable movement to said shaft means to simultaneously move said disc elements either into or out of engagement with the corresponding one of said fixed contact means to selectively connect or disconnect said fixed contact means for current flow t therebetween.
 14. A radio frequency transfer switch of the character set forth in claim 13, wherein said contact faces of said annular fixed contact means are each inclined to define a concave seat for the corresponding one of said disc contact elements.
 15. A radio frequency transfer switch of the character set forth in claim 14, wherein said disc contact elements are provided with slit means to facilitate deflection of the discs into substantial conformity with said concave seats of said fixed contact means upon engagement therebetween.
 16. A radio frequency transfer switch of the character set forth in claim 15, wherein said conductor and spacer means is provided with longitudinally extending cooling fin means.
 17. A radio frequency transfer switch of the character set forth in claim 13, wherein said means releasably and adjustably interconnecting said conductor and spacer means and said disc contact elements with said shaft means includes thread means on said shaft means, a cooperatively threaded axial bore in said conductor and spacer means to receive said shaft thread means, and means for releasably interengaging said conductor and spacer means and said shaft means in a desired position of said conductor and spacer means longitudinally of said shaft means. 